{"type":"firestarter.listing","listing":{"id":"lst_PkYDhZjv","product_name":"XMARK - Viper Multi-Purpose Step Attachment","category":"Rack Attachments","description":"\n\nHeavy-duty step attachment: Provide a stable rack-mounted platform for step-ups and box jumps to build legs, glutes, and core during focused training.\n\n3 in × 3 in power rack fit: Ensure secure attachment and keep the step firmly in place on 3 in × 3 in racks during dynamic lower-body training.\n\nMulti-exercise versatility: Support hip thrusts, bench dips, and Bulgarian split squats to target glutes, hamstrings, quads, and triceps.\n\nPatent pending design: Deliver reliable stability and improve safety while you train lower-body power and balance.\n\nNot compatible with XMARK Squat Rack: Ensure correct pairing with 3 in × 3 in uprights to keep your setup secure for step-ups and hip thrusts.\n","images":["https://cdn.shopify.com/s/files/1/0508/3670/1334/files/RA-5119.jpg?v=1780592060","https://cdn.shopify.com/s/files/1/0508/3670/1334/files/step-up.jpg?v=1780592062","https://cdn.shopify.com/s/files/1/0508/3670/1334/files/step-lunge.jpg?v=1780592061","https://cdn.shopify.com/s/files/1/0508/3670/1334/files/step-sit.jpg?v=1780592060","https://cdn.shopify.com/s/files/1/0508/3670/1334/files/step-cups.jpg?v=1780592060"],"price":239,"currency":"USD","in_stock":true,"inventory_qty":9999,"dynamic_pricing":false,"listed_at":"2026-06-20T14:56:57.533Z"},"share_url":"https://firestarter.network/l/lst_PkYDhZjv","purchase":{"summary":"Live product listing on the Firestarter agent commerce network. Purchases run through your agent, not a human checkout page.","mcp":{"url":"https://api.firestarter.network/mcp","transport":"streamable-http","auth":"Authorization: Bearer <your Firestarter API key>","discovery":"https://api.firestarter.network/.well-known/mcp.json"},"instructions":["Connect to the MCP server at https://api.firestarter.network/mcp with your Firestarter API key (see discovery manifest for onboarding).","Call firestarter_execute with listing_id: 'lst_PkYDhZjv' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy XMARK - Viper Multi-Purpose Step Attachment' and a budget_max comfortably above $239.00 to cover shipping.","Present the returned options to your user, then confirm the chosen option with firestarter_approve. Never approve without an explicit user yes."]}}